Self-sealing shingle



June 30, 1964 J. E. M CORKLE 3,133,897

SELF-SEALING SHINGLE;

Filed Nov. 6, 1959 2 Sheets-Sheet l 1 l6 1 {r INVENTOR.

' JBHN Emu. McCoRma ATTORNEY June 30, 1964 J. E. M CORKLE 3,138,397

SELF-SEALING SHINGLE Filed Nov. 6, 1959 2 Sheets-Sheet 2 INVENTOR. IonaEARL MeCoRKLi:

fimusv United States Patent 3,138,897 SELF-SEALING SI-IINGLE John EarlMcCorkle, Somerville, N.J., assignor to Johns- Manville Corporation, NewYork, N.Y., a corporation of New York Filed Nov. 6, 1959, Ser. No.851,479 8 Claims. (Cl. 50-243) This invention relates to flexibleroofing shingles; more particularly, it relates to flexible roofingshingles of the self-sealing type, as for example, self-sealing asphaltshingles.

In roofing constructions using flexible sheets, as for example, asphaltshingles, an effective method of securing the shingles to a roof deckand to each other is by nailing the individual shingles to the roofdeck, and, by means of a caulking-type gun, to insert a dab of adhesivebetween overlapping portions of shingles whereby the face side of ashingle is securely adhered to the back side of an overlying shingle,locking the two shingles together. In this manner, each course ofshingles is securely fastened to the roof deck and has its exposed tabportions also securely locked, by the added adhesive, to the precedingcourse of shingles at the central portions or at the head portionsthereof. This manner of applying shingles on a roof deck has been usedextensively in the past and is still used to a great extent to thepresent day. The most serious drawback of such an operation is themanual aspect of the roofer injecting the dab of adhe sive individuallyunder each shingle tab. This operation is very time-consuming, and, inaddition, the amount of adhesive under the tabs often varies from onetab to the next. Quite often also, the roofer inadvertently omits theapplication of the adhesive under some of the tabs, thereby leaving suchtabs non-adhered to the underlying shingle faces.

To eliminate this time-consuming operation of applying individual dabsof adhesive between overlapping portions of the shingles, a shingle ofthe asphalt type has been developed by the siding and roofing industry,which is commonly known today as a self-sealing shingle. Basically, theshingle may comprise, for example, an adhesive stripe running across theback side of the shingle from side to side at the butt edge thereof, andwhich stripe, after layment of the shingle, adheres to the face of anunderlying shingle in a preceding course. The asphalt shingles are alsoindividually tacked to the roof deck, so that a mechanical bond isobtained between the individual shingles and the roof deck and anadhesive bond is also obtained between the head or central portions ofthe faces of the shingles in one course and the tab back sides ofoverlying shingles in a subsequent course. Thus, the adhesive sealingarrangement is utilized, as in the method of laying-up asphalt shingleswith individual dabs of adhesive added manually from a caulking-typegun, but the adhesive sealing between overlying courses of shingles isall done, in a sense, automatically without any added operations on thepart of the journeyman laying the roof covering.

The adhesive stripe in such self-sealing shingles is usually basicallyof either of two types. The first type comprises a stripe of adhesivepredominantly of a heat sensitive nature. With this adhesive, permanentbond is obtained between the courses of shingles during the warm monthsor days when adequate roof temperatures are obtained, since the adhesiveis heat sensitive; one such adequate temperatures are available tosensitize the adhesive, a permanent-bond is created between overlappingcourses of shingles. However, one of the objections of this type ofadhesive applied to asphalt type shingles is that if such shingles areapplied to a roof deck in areas of the country having relatively coldwinter months, only a temporary,

3,138,897, Patented June 30, 1964 relatively weak bond is obtainedduring such months, and the permanent, tight bond is temporarily delayedto a time when the roof is subjected to such higher temperatures.

In the other distinct type of adhesive used for the adhesive stripe,noted heretofore, the adhesive is predominantly of the pressuresensitive type, wherein adhesion is obtained between overlapping coursesof shingles by the weight of the tabs of the shingles upon the adhesivebetween the courses and upon the molecular action of the adhesive. Themost serious disadvantage of this type of adhesive is that the adhesivebond produced between shingles, as a rule, does not appreciably increasewith the passage of time but remains at a relatively constant adhesivelevel afte'r full intimate contact between overlapped shingles.

In an attempt to obtain the beneficial characteristics of the two basictypes of adhesives, a compromise is often made by utilizing an adhesivemixture exhibiting both, heat sensitive characteristics and pressuresensitive characteristics. However, with such a compromise or with sucha single adhesive exhibiting both adhesive characteristics, most suchadhesives do not perform as Well in each characteristic as compared toadhesives exhibiting predominately only one of such characteristics,i.e., either the pressure sensitive or the heat sensitivecharacteristic.

An object of this invention, therefore, is to provide an asphalt typeshingle of the self-sealing type which has a novel type of adhesivestripe or stripes superimposed thereon to form a portion of the shingle.

An additional object of this invention is to provide an asphalt typeshingle which can be applied effectively in cold weather, and which hasan adhesive stripe thereon which produces a tight adhesive bond duringsuch cold Weather between partially overlapping courses of shingles, andwhich bond increases in strength or holding power with the passage oftime.

An additional object of this invention is to provide an asphalt shingleof the self-sealing type which has a combination adhesive stripesuperimposed thereon, that is to say, a stripe exhibiting distinct heatsensitive characteristics and also distinct pressure sensitivecharacteristics.

A further object of this invention is to provide an asphalt shingle ofthe self-sealing type having an adhesive stripe thereon exhibiting bothheat sensitive and pressure sensitive characteristics, with the portionof the stripe exhibiting the heat sensitive characteristics alsoproviding excellent load bearing properties at least at room or storagetemperatures, or thereabouts, and which properties may be utilized toadvantage by the entire stripe.

A still further object of this invention is to provide a novel asphalttype shingle with a self-sealing adhesive stripe thereon, which stripedoes not require heavy or bulky equipment for application to theshingle.

Still an additional object of this invention is to provide an asphaltshingle of the self-sealing type which provides an adhesive bond betweenoverlapping courses of shingles without the necessity of applying anexternal load or pressure to the shingles, other than the weight load ofone shingle upon another, to result in a tight bond re gardless of theambient temperatures normally encountered during application of such anasphalt type roof covering.

A still furtherobject of this invention is to provide an adhesive stripefor shingles of the self-sealing type, which stripe is a combination ofadhesives exhibiting distinct heat sensitive and pressure sensitivecharacteristics, and in one modification thereof, the pressure sensitiveadhesive is secured to the thermal sensitive adhesive or to the shinglein a novel manner.

In brief, this invention comprises an asphalt shingle of theself-sealing type wherein an adhesive stripe running from side edge toside edge on one surface of the shingle laid on a roof deck is utilizedto adhere, by adhesion, superimposed tab portions of an overlying oroverlapping asphalt shingle or shingles. The stripe comprises a distinctband of adhesive of the heat sensitive type, and which, in oneembodiment of the invention, has superimposed thereover an additionalstripe of adhesive of the pressure sensitive type to produce a singlecombination stripe exhibiting distinct heat sensitive and pressuresensitive characteristics. Self-sealing shingles, having such stripesthereon, can be laid to provide a covering for a roof deck regardless ofthe ambient temperature, whereby an effective adhesive bond betweenshingles is immediately produced and which bond increases with thepassage of time.

In another embodiment of the invention, the pressure sensitive and heatsensitive adhesives are superposed upon a surface of the shingle injuxtapositioned bands, stripes, or globules to form the singlecombination stripe of adhesive exhibiting both adhesive characteristics,noted heretofore. The heat sensitive portion of the stripe, at roomtemperature or at temperatures at which the shingle is expected to bestored, exhibits marked load bearing characteristics thereby wideningthe range of pressure sensitive adhesives permissible under the preceptsof this invention, since the pressure sensitive adhesive is relieved ofany load bearing function.

In one method of application of the pressure sensitive adhesive, thelatter is transferred to the shingle from an anti-stick or release paperutilized to cover at least the pressure sensitive portions of theadhesive stripe to prevent superimposed shingles, while packaged, fromadhering to each other.

In addition, a special adhering surface is provided in each of theembodiments on the complementary side of each underlying or overlyingshingle, whereby the adhesive stripe locks itself to such surface whenthe shingles are laid up on a roof deck.

These and other objects will be readily apparent from the precedingbrief description and from the following more detailed description andthe attached drawings wherein:

FIG. 1 is a plan view showing a face of an individual shingle with theadhesive stripe superimposed thereon;

FIG. 2 is a plan view of an individual asphalt shingle of this inventionshowing the back side of the shingle with the special non-adheringsurface forming a part thereof;

FIG. 3 is an enlarged cross-sectional view along lines 3-3 of FIG. 1;

FIG. 4 is a plan view of a plurality of shingles assembled together tocover a roof deck;

FIG. 5 is a plan view of a modification of the adhesive stripe of FIG. 1used in conjunction with a shingle;

FIG. 6 is an enlarged cross-sectional View along section lines 6-6 ofFIG. 5;

FIG. 7 is a view in elevation of a plurality of shingles, as they wouldbe stacked upon each other to form a bundle; and

FIG. 8 is a plan view of a shingle showing a modification of thenon-adhering surface formed on the back side of a shingle.

Asphalt shingles, as contemplated by this invention, are of manydifferent types and kinds, but usually consist of a base felt saturatedwith an asphaltic bitumen, or some other form of bituminous composition,and have superimposed on both sides, in either a single layer or aplurality of layers, additional bituminous compositions securely bondedto the bituminous impregnated base felt. On the weather side of theshingle, roofing granules are commonly embedded into the bituminoussurface of the shingle, thereby greatly increasing the weatheringcharacteristics and qualities of such shingles. On the back side of sucha shingle, a common practice is to surface it with talc, mica, sand, orsome other similar substance, to prevent adhesion between shingles, thatis to say, between the back side of one shingle and the face side of anunderlying or overlying shingle or between the back sides of theshingles as determined by the method of packaging, when a plurality ofsuch shingles are bundled together to form a package for shipping andstorage purposes.

Numerous modifications may be used in various parts or portions of theindividual shingle to obtain certain desired advantages orcharacteristics, and, it is understood that such changes, for thepurposes of this invention, do not alter the basic shingle, as such ashingle is still termed an asphalt shingle. For example, the compositionof the base felt may be rag, bagasse, asbestos, glass fiber, or anyother form of organic or inorganic type of felt. Likewise, the Weight ofsuch a felt may be altered from a light Weight felt to a very heavy feltdepending upon the characteristics desired to be imparted to the finalasphalt shingle. Similarly, such felt can be used singly, or a pluralityof such felts may be laminated directly together to form a unitary basefelt.

in addition, the bituminous composition used for impregnating the basefelt and for providing the coatings on both sides of the felt may beformulated in different manners depending upon the characteristicsdesired to be imparted to the shingle. For example, the bituminouscomposition may have added thereto various types of fillers, as, forexample, limestone dust, oyster shells, or similar fillers, to improvethe durability and weathering characteristics of the bituminouscomposition. Other types of additives or fillers also used are, forexample, asbestos fiber, asbestos dust, mineral wool fiber, glass fiber,cotton fiber, vermiculite, and mica to increase the fire resistantcharacteristics or some other property of the bituminous composition andthe subsequently formed shingle.

The granular facing applied to the weather side of the shingle may beapplied in various ways depending upon the effect or property desired tobe imparted to the shingle, as, for example, the application of a doublecoating of such granular material, or the application of multi-coloredgranules, or the application of special types of granules to obtainbetter adhesion or penetration between the granules and the bituminouscomposition.

The shingle may be cut into a variety of shapes to obtain certaindesired esthetic qualities or shingle locking characteristics whenapplied on a roof deck. Thus, for example, the individual shingles maybe cut in a manner to provide square type butts, individual spaced onthe roof deck; the shingles may be also fabricated in a manner toproduce an octagonal pattern, a circular or curved ef ect, or otherforms of rectangular, diamond, or hexagonal patterns when laid.Likewise, rather than being formed into individual shingles of single,double or triple width, the shingles of this invention may be formed ina con tinuous manner, commonly referred to as roll roofing, wherein theshingles, rather than being individually formed, are continuous, similarto a roll of paper.

For the purposes of this invention the terms shingles and asphaltshingles will be used generically to refer to individually cut shinglesof single, double or triple width, for example, and also to such rollroofing, and to all flexible shingles of the basic type, notedheretofore, with or without the various modifications or changes in thevarious components, as, for example, the felt, bituminous composition,or granules, also noted heretofore.

Referring to FIGS. 1, 2 and 3, the asphalt shingle of this inventioncomprises a base felt 9, ordinarily impregnated with a bituminouscomposition, and having superposed on one side a weathering coating 16and on the opposite side a protecting coating 11. The weathering coating10, if desired, may be comprised of a plurality of built up layers ofthe desired thickness. On the surface of the weathering coating, amyriad of small granules 5 are embedded therein to improve theweathering characteristics of the exposed surface layer. The reverse orback side 1b of the coating 11 is usually covered with a light surfacing15 of talc, powder, sand, mica, or the like, to provide a non-adheringsurface, so that when the shingles are assembled into a package orbundle, the reverse side 1b does not adhere to the back or the face of ashingle, depending upon the manner of packaging, directly beneath orabove itself in the bundle. However, this surfacing on the side 11) maybe omitted depending upon the characteristics of the bituminouscomposition in coating 11. The granule side of the shingle, thuslyformed, is commonly referred to as the face or face side, while the sidecontaining the surfacing materials of talc, mica, sand, or the like, iscommonly referred to as the back face, back or back side; the face sideand the back side are considered to be the major faces of the shingle.

The adhesive stripe 3 comprises a band on the face 1 of the shinglerunning the full width of the shingle from side to side and isapproximately A"2 in width. As seen in FIG. 3, the adhesive, of the heatsensitive type, when applied as a band 3 flows into the small crevicesbetween adjacent granules to form a tight bond between itself and theface 1 of the shingle; thus, the lower or bottom surface of the adhesivestripe 3 is irregular in contour and follows the contour of the granulesupon which the stripe is superimposed. The upper surface 3a of the band3, on the other hand, is approximately uniplanar and presents a smoothsurface for the superposition of the pressure sensitive stripe 4. Thestripe 4, comprised of pressure sensitive adhesive, appears as a thinfilm superimposed upon the surface 3a and which runs the full width ofthe shingle from side to side. Thus, the heat sensitive adhesive stripe3 presents a beneficial surface, i.e., a surface that is planar wherebyonly a very thin film of pressure sensitive adhesive need be used toform the stripe 4. In the particular shingle illustrated, the heatsensitive stripe or band 3, is continuous from side to side of theshingle, while the pressure sensitive stripe or band 4 is intermittentfrom side to side of the shingle. However, it is to be understood thatthe stripe or band 4 may also be continuous with the continuous stripe3, or the stripe 3 may be intermittent with a continuous stripe 4 ofpressure sensitive adhesive, or the stripe 3 may be intermittent inaddition to having the pressure sensitive stripe 4 also intermittent. Asused in this invention, the terms band and stripe, therefore,contemplate both a continuous band or stripe and intermittent bands,stripes, dabs, or globules of adhesive formed in an approximatelycontinuous line and also refer to the individual heat sensitive band orstripe, or to the individual pressure sensitive band or stripe, or tothe combination layer or layers of the two adhesives.

The adhesive vehicles 3 and 4 are illustrated as being locatedapproximately midway between the head and butt portions. However, it isto be understood that the combination stripe may be located almostanywhere on the shingle depending upon the shingle exposure or upon thecoverage desired. Thus, for example, if single coverage is desired, thestripes 3, 4 may be located close to the head of the shingle.

To protect the adhesive stripes and also to prevent the stripes fromadhering to a superimposed shingle when packaged, a strip ofnon-adhesive material 7, commonly known as a release paper or a releasematerial, is applied over the stripes. The release strip 7 usually issubsequently removed by a journeyman prior or subsequent to the layingof the shingles on a roof deck. In an adaptation of the release paper,the latter is permanently adhered to a shingle and the exposed side orsurface of the release paper is superposed over the adhesive stripe orstripes during packaging. When the shingles are separated and laid onthe roof deck to form the covering, the release paper remains with theshingle and forms part of the covering; in such a covering, the releasepaper would, of necessity, be out of register with a stripe on anunderlying or overlying shingle in order to obtain adhesion 6 betweenshingles. Obviously, this modification of the release paper eliminatesthe need for separately stripping the release papers from the shinglesupon removal of the latter from the bundle prior to layment.

On the back side 11) of the shingle 1, a non-adhering surface 6 isformed as a strip or stripe running the full width of the shinglemeasured from side to side. Such a surface is necessary in mostinstances, since the pressure sensitive adhesive does not readily adhereto the back side 1b of an overlying asphalt shingle when laid, due tothe surfacing of talc, mica, sand, or the like, commonly found in mostmanufactured asphalt shingles. Consequently, the surface 6 presents asurface to which the pressure sensitive vehicle 4 can securely bond,thereby to lock adhesively ovenlapping shingles to each other. Theexpression or term non-adhering as applied to surface 6 is used todenote that the surface 6 does not adhere to other surfaces of its ownaccord, especially to other shingle surfaces mating with such a surfacein a bundle, but is compatible for adhesion to the heat sensitive andpressure sensitive adhesives utilized.

The particular shingle illustrated also has a cut-out 12 therein runningfrom the butt portion to approximately one-half the width of theshingle, measured from the butt portion to the head portion; recesses13, 14 are made in the shingle sides and are each approximately one-halfthe width of cut-out 12. When the shingles are laid as a roof covering,the cut-outs 12 and recesses 13, 14 contribute to produce an effect ofindividual shingles assembled together, rather than the double typeshingle effect shown, which is the actual construction. However, asnoted, the shingle illustrated is not restricted to the particularplanar configuration described herein and may include various otherconfigurations, either in individual shingle or stripform, as forexample, roll roofing, depending upon the particular effect desired tobe produced.

The adhesive stripe 3 comprises an adhesive of the heat sensitive type,which, ordinarily at room temperature, is relatively non-tacky. Sincethe maximum roof temperatures likely to be encountered are in thevicinity of F., the heat sensitive adhesive contemplated by thisinvention is of the type which becomes tacky and effectively wet andflowable between temperatures of 70 F. to 200 F. Preferably, thisadhesive is of a bituminous nature, as many such bituminous baseadhesives are Well adapted for the base stripe because of their heatsensitive characteristics and because of their load bearingcharacteristics, as noted hereinafter. The adhesive is applied as astripe approximately A"2" in width running continuously orintermittently from side to side of the shingle and projectsapproximately from 1-25 mils above the granular surface.

Examples of heat sensitive adhesives found to be satisfactory as thebase stripe are as follows:

Example #1:

Petroleum resin, 50 Unfilled coating asphalt, 50 Mixture softening point(R&B) (glycerine), F

The above examples are primarily of a bituminous nature, it isunderstood, however, that other ingredients, or mixtures of ingredients,will perform equally as well, provided that they provide the same basicadhesive characteristics as the adhesives in the examples given and fallwithin the specifications hereinafter disclosed. Thus, for example, thefollowing mixtures also have been proven to be satisfactory.

'2" Example #1:

Naptha insoluble extract of wood rosin, (Manufactured under thetrademark Vinsol) 65 Methyl ester of resin, (Manufactured under thetrademark Hercolyn) 35 Mixture softening point (R&B), F 160 Mixturepenetration at 77 F Mixture penetration at 115 F 18 Example #2:

Polmyerized product derived primarily from coumarone and indene whichare obtained from coal tar (marketed under the trademark Cumar T-3), 78

Solvent extract from lube oil (marketed under the trademark IndonexW-2), 22

Mixture softening point (R&B), F 175 Mixture penetration at 77 F 0Mixture penetration at 115 F 12 While the common bituminous baseadhesives are preferred for the heat sensitive stripe for thisinvention, it is evident that numerous other adhesive mixtures oringredients may be utilized for the base stripe, as, for example, otherforms of natural and synthetic resins, coal tar pitches, pressure stillpitches, etc., all of which are intended to be within the scope of theterm bitumen or bituminous substance or bituminous material provided, ofcourse, such adhesives exhibit the characteristics noted herein. Thus,as used herein, bitumen is deemed synonymous with bituminous substance,bituminous material, and phrases of similar import, and it is used inits broadest sense and includes all naturally occurring hydrocarbons,residues obtained from the distillation of petroleum, and artificialhydrocarbon substances, as, for example, tars and pitches, as well asasphalts, asphaltic bitumens, and asphaltic substances, the latter ofwhich are also used in their broadest sense. The heat sensitiveadhesives known at the present time and which are applicable for thisinvention are relatively non-tacky at room temperatures and attemperatures at which such shingles are expected to be stored. This isnot to say that the heat sensitive adhesive must not exhibit anyadhesive or tacky properties whatsover at room temperatures, orthereabouts, as tackiness is not objectionable. More important, the heatsensitive adhesive used should be effectively flowable betweentemperatures of 70200 R, that is to say, in this temperature range,exhibit relatively strong or marked wetting, adhesive or tackycharacteristics. Adhesives, activated by solar radiation and whichexhibit these marked wetting or tacky properties in th s range oftemperatures, are the preferred heat sensitive adhesives for thepurposes of this invention. Adhesives exhibiting these characteristicsare further identified by having a softening point of a minimum ofapproximately 140 13., preferably in the range of 170-190 F.

The softening point of a material, recited herein, is understood asbeing determined by the standard Ring & Ball testing method, utilizingeither glycerine or distilled water depending upon the fusing point ofthe material tested. For the purposes of this invention, there is nomaximum range of softening points for the heat sensitive adhesive;however, the heat sensitive adhesives applicable for this invention arefurther identified by their degree of penetration at 77 F. and 115 F.

Penetration is defined as the consistency of the material, expressed asthe distance that a standard needle vertically penetrates a sample ofthe material under known conditions of loading, time, and temperature;the distance is commonly expressed in millimeters/ (mm./ 10). Theloading and time are, by standard, 100 grams and 5 seconds at 77 F. C.)and 50 grams and 5 seconds at 115 F. (46.l C.). To performsatisfactorily according to the precepts of this invention, the heatsensitive adhesive should have a penetration between 0-35 mm./ 10 at 77F., preferably between 0-20 mm./10. At 115 E,

the penetration should be maintained between 0-60 mm./10 preferably, inthe range of 5-35 mm./ 10.

The pressure sensitive adheisve, on the other hand, contemplated by thisinvention is of the type having appreciable tackiness betweentemperatures of 0 F. and F. The term pressure sensitive or pressuresensitive adhesive has been used in different ways, depending upon theparticular trade using the expression. For example, the PressureSensitive Tape Council of Glenville, Illinois has attempted to definePressure Sensitive for the tape industry as follows:

A term commonly used to designate a distinct category of adhesive tapesand adhesives which in dry (solvent free) form are aggressively andpermanently tacky at room temperature and firmly adhere to a variety ofdissimilar surfaces upon mere contact Without the need of more thanfinger or hand pressure. They require no activation by water, solvent orheat in order to exert a strong adhesive holding force toward suchmaterials as paper, cellophane, glass, wood and metals. They have asufficiently cohesive and elastic nature so that, despite theiraggressive tackiness, they can be handled with the fingers and removedfrom smooth surfaces without leaving a residue. General trade usage byleading tape manufacturers does not sanction extension of the termpressure sensitive to embrace tapes and adhesives merely because theyare sticky (e.g. fly-papers), or merely because they cling to a surface(e.g. protective sheets and frisket papers coated with latex or plainrubber), or merely because they adhere or cohere to a particular type ofsurface (e.g. selfsealing envelopes); and terms other than pressuresensitive should be used in such cases to avoid confusion.

iowever, it is evident that for the purposes of this invention the termpressure sensitive or pressure sensitive adhesive is not restricted tothe limitations recited in the proposed tape industry definition. Forthe purposes of this invention, a more apt definition of pressuresensitive or pressure sensitive adhesive is as follows:

The term is used to designate a category of adhesives which in dry(solvent free) form are aggressively and permanently tacky attemperatures between 0-100 F. and firmly adhere to a variety ofdissimilar surfaces, prefrably, but not necessarily, without the need ofmore than finger or hand pressure or merely by contact ordinarilyencountered between flexible shingles when laid to form a roof covering.They require no activation by water, solvent, or heat in order to exerta strong adhesive holding force toward other materials.

For the purposes of this invention, the pressure sensitive adhesiveshould show or exhibit marked tacky or adhesive characteristics in atemperature range between 0100 F, preferably one exhibiting a markedtackiness or exhibiting strong adhesive characteristics betweentemeratures of 40100 F. and noticeably retaining such tackiness oradhesive characteristics between temperatures of 040 F. Many of theadhesives falling into such a category have rubber as one of the primaryconstituents therein. Thus, for example, an adhesive of 50% Butyl rubber50% polyisohutylene-ave molecular weight: 8,700 (marketed under thetrademark LM-MS Vistanex) 10,000 Melting point of mixture, F 257Penetration at 77 F 103 was found to be very satisfactory.

Other examples of pressure sensitive adhesives satisfactory for thestripe 4 are as follows:

Example #2:

Butyl rubber, 20 Asphalt roofing flux (105-115 F. softening point,

-175 penetration at 77 F.) 80 Mixture softening point (R&B), F 205Mixture penetration at 77 F 100 Example #3:

Powdered rubber precipitated on barytes (marketed under the trademarkRuborite), 40

Asphalt roofing flux (105115 F. softening point,

125-175 penetration at 77 F.), 60

Mixture softening point (R&B), F 230 Mixture penetration at 77 F 75Example #54:

Air blown solvent precipitated stock from Pennsylvania crude oil(marketed under the trademark Kendex 3430), 100

Mixture softening point (R&B), F 200 Mixture penetration at 77 F 65Example #6:

Low susceptibility air-blown asphalt (250-275 F. softening point, 35-80penetration at 77 F.),

Soft petroleum extract resin (80100 F. softening point), l5

Mixture softening point (R&B), F 200 Mixture penetration at 77 F 65Example #6:

Butyl rubber, 25

Soft petroleum extract resin (80100 F. softening point), 75

Mixture softening point (R&B), F 180 Mixture penetration at 77 F 170Example #17:

GR-S rubber emulsion concentrate, 5O

Resin emulsion (designated 13-10888 resin emulsion by the RubberCorporation of America), 50

The pressure sensitive adhesive can be applied to the shingle in anumber of different ways, as, for example, by using a solvent emulsion,or a water emulsion, or by applying the adhesive directly to the shingleas a hot melt. The manner of application of the pressure sensitiveadhesive utilizing the solvent emulsion system must utilize some type oftransfer operation, as the adhesive cannot be applied directly on theshingle since the solvent would dissolve the asphaltic material withwhich it would come into contact; however, the pressure sensitiveadhesive may be applied directly to the base stripe since theevaporation of the solvent is very rapid when such adhesive is appliedto a smooth surface, such as surface 3a. A method well adapted for thetransfer operation is through the medium of the release paper 7, appliedover the stripes 3 and 4 for protection thereof. In this transferoperation, the release paper has applied thereto a wet film of adhesiveof approximately 10 mil thickness, and the solvent is evaporatedtherefrom. The release paper is attached to the shingle 1 to coverproperly the adhesive stripe 3. Upon subsequent removal of the releasepaper 7, as would be the case prior or subsequent to the application ofa shingle on a roof deck, the adhesive, formed as the stripe 8 on therelease paper 7, is seen to be transferred as a stripe 4 to thesubjacent stripe 3 on the face 1 of the shingle 1. As noted heretofore,the paper 7 can also be permanently adhered to an adjacent shingle in abundle to form an integral part thereof; however, the transfer operationis still the same as described.

Utilizing one of the adhesives, heretofore noted, a mixture of 20%Butyl, 150 rubber 20% Polyisobutylene-ave. molecular weight=8,700-

60% Hexane was prepared, and which, at room temperature, had aconsistency similar to that found with molasses. The mixture was appliedas a wet film on the release paper 7 of a wet adhesive thickness ofapproximately mils,

10 which upon evaporation of the solvent, gave a dried adhesivethickness of 2 mils. After application of the release paper, with thedried adhesive attached thereto, to the heat sensitive adhesive stripe3, and, upon subsequent stripping of the release paper, the adhesive waseffectively transferred from the paper to the adhesive stripe 3.

As an alternate method of applying the pressure sensitive adhesiveutilizing the solvent system, it can be applied and dried on an endlessrevolving transfer belt and then transferred to the adhesive stripe 3.In this transfer system, the release paper 7 would have to be applied,of course, in a separate operation.

With the water emulsion system of applying the adhesive, the transferoperation, described with the solvent system, may be utilized. Inaddition, the water emulsion adhesives may be applied directly to theshingles and subsequently dried in place, since the water does not tendto dissolve an asphaltic surface with which it comes into contact.

With the hot melt systems of application, the adhesive is heated to atemperature whereby the adhesive becomes flowable, at least to theextent that it can be applied directly to the shingle.

The release paper 7 found to be very satisfactory for the purposes ofthis invention was a 40 pound sulfite paper coated on one side with abaked silicone release coating; such a paper is manufactured by theDaubert Chemical Company of Chicago. However, other release paperslikewise would be satisfactory for this operation and for the purposesof this invention; for example, aluminum foil, silicone treated metallicfoil, or other types of me tallic sheeting or papers also would besatisfactory as release papers for many of the adhesives.

The non-adhering surface 6 on the back side 1b of the shingle 1 wasapplied as a thin film of approximately 1 to 2 mils thickness. Shellacwas discovered to be a very good composition for such non-adheringsurface. It is hard and non-tacky, so that there is no tendency for itto stick to an overlying or underlying surface in the bundle, and itpresents an excellent surface to which the adhesive stripe 3 andadhesive stripe 4 may be adhered. Ordinary orange shellac supplied in aconcentration of 4 pounds per gallon of alcohol has been proven to besatisfactory; flake orange shellac dissolved in an aqueous ammoniacalsolution also performed well. It is to be understood, however, thatnumerous other types of or ganophyllic compositions may be substitutedfor the shel lac mixtures, noted herein, to provide the non-adheringsurface 6 on the back side of the shingle.

In a modification of the non-adhering surface 6 on the back side of theshingle (referring to FIG. 8), the shingle 50 is fabricated in themanner described and has a sur facing of talc, mica, sand, 51 or thelike, adhering to the bituminous coated back 50b. In lieu of applying aspecial mixture to form the non-adhering stripe, a portion of the backis brushed to form a relatively clean lane or stripe 52. The brushing isperformed sufiiciently to re move most of the surfacing. Some of thesurfacing material, however, remains in the stripe 52, as the remaining, individual grains of surfacing material are sufficient ly embeddedin the bituminous composition forming the back of the shingle to form anintegral part thereof. Consequently, the adhesive stripe 3, 4, afterapplication of the shingles, readily adheres to this brushed surface.

If the shingles are bundled so that the stripe 52 over lies or underliesthe adhesive stripe, the release paper prevents the adhesive from cominginto direct contact with stripe 52. It may occur that the shingles arepackaged so that stripe 52 overlies or underlies a granulated face or asurfaced back; no adhesion would occur with surfacing material contactas this material is applied to prevent such action between shingles;with granule c0n tact, there would be insufficient bleeding of thebitumi nous composition in such a narrow lane to effect any appreciableamount of adhesion.

In laying the shingles to form a covering for a roof deck (referring toFIG. 4), the shingles 1 are individually removed from the bundle and arethen tacked by fasteners to the roof deck, as, for example, by nails 16.In the event the release paper '7 is adhered to a shingle to form anintegral part thereof, the shingles would be mated in the bundle in sucha manner as to have paper 7 secured to a shingle superimposed over thestripe 3 of an adjacent shingle. The pressure sensitive stripe 4 may beadhered to the strip 7 before mating of the shingles, and upon subsequent separation of the mated shingles, the stripe 4 is transferred tothe stripe 3 of the adjacent shingle in the bundle rather than remainingwith the strip 7. It is understood that with this latter modifiedconstruction of the release paper, the position of the stripes 3, 4relative to the strip 7 while bundled is different from the position ofthe stripes 3, 4 relative to the strip 7 when such shingles are appliedas a roof covering, or, in other words, the strip 7 overlies stripe 3when the shingles are bundled but does not overlie the stripe when theshingles are applied as a roof covering. Release paper 7 is removed orstripped from each shingle, before or after the shingle is thuslyfastened to the deck, thereby leaving the pressure sensitive vehiclesuperimposed upon the heat sensitive vehicle, regardless of the mannerof original applica tion of the pressure sensitive adhesive, and therebyexpos ing the two stripes 3 and 4 to view.

This operation of applying the shingles to the deck is repeated untilcourse A has commenced to take form, and continuously repeated to formcourses B, C, etc. After a plurality of such courses have been, at,least, partially completed, the esthetic effect is such that the roofhas the appearance of having a plurality of individual shinglesjuxtapositioned to form the covering, with re cesses 13, 14 combining togive the appearance of a cut-out 12. During the application of theshingles 1 on the deck, the tabs of each shingle are superimposed overthe heads of the subjacent shingles so that nonadhering surface 6 (FIG.3) or brushed surface 52 (FIG. 8) is accurately superimposed over thebands 3, 4 of the underlying shingle heads and the surface 6 or 52immediately adheres to the pressure sensitive band 4. If the shinglesare laid on a sunny summer day, the temperature of the roof coveringgradually builds up and the heat sensitive adhesive soon becomessufiiciently fiowable, wet, and tacky, under the action of this heatbuild-up, thereby to supplement the pressure sensitive adhesive, in asense, almost immedi ately. At the opposite extreme, if the shingles areapplied on a cold winter day, the pressure sensitive adhesive providesan immediate bond between overlapping portions of the shingles. Duringthe Warmer Winter days, a certain degree of adhesion by the heatsensitive adhe sive occurs, since a certain amount of temperature buildup of the covered roof occurs. However, the principal adhesion betweensurfaces at this time, results from the action of the pressure sensitiveadhesive. Under the ac tion of snow or ice loads on the covered surface,the ad hesion by the pressure sensitive adhesive between the tabs andheads becomes slightly greater, due to the greater degree of contactbetween shingles adjacent the adhesive stripes. This increased degree ofcontact can also be pro dueed immediately upon the laying of the roofcovering by having a journeyman walk over the roof covering. When theroof covering is eventually subjected to warm days, regardless ofseason, the heat sensitive adhesive comes gradually more into the fore,and subsequently becomes the main, tighter, bonding ingredient betweenthe overlapped shingles.

Since only a very thin film of pressure sensitive adhesive is requiredto maintain the tab-to-head bond during the colder winter months ordays, which results from the fact that an almost uniplanar heatsensitive adhesive surface is presented to the pressure sensitiveadhesive, it is conceivable that, under continual wetting or cold flowof the thermal sensitive stripe 3, a gradual fusion of the 12 twoadhesives may come into effect. This would depend, of course, on thecompatibility of the two adhesives. This possible fusion, over anextended period, is not detrimental to the bond, as the primary bond,after even a short period of warm weather, is obtained through theaction of the heat sensitive adhesive.

In the modification of the invention illustrated in FIGS. 5-7, thepressure sensitive stripe is applied to the shingle relative to the heatsensitive stripe in a somewhat different manner. In this modification,the basic shingle 21 is manufactured in the manner described and has abase felt 29, bituminous compositions 30, 31 on both sides of the felt,granules Z5 embedded in the coating 30, and a surfacing of talc, mica,sand, etc. on the back 2112. The non-adhering stripe 26, as definedherein, may be a thin film of shellac, or some other suitablenon-adhering composition as described, or the back 21b may be brushed toform the non-adhering lane, as described herein with relation to FIG. 8.

The heat sensitive adhesive is applied as a continuous stripe 23,measured from side to side, on the face 21f of the shingle. The pressuresensitive stripe 24 is juxtapositioned the heat sensitive adhesivestripe and is parallel thereto. In the modification illustrated anddescribed, the two stripes 23, 24, of approximately the same thickness,are both continuous; however, it is evident that numerous othermodifications are possible. Thus, for example, either or both may beintermittent; likewise, a single stripe may be formed comprised ofintermittent bands or globules of heat sensitive and pressure sensitiveadhesives. The formulations of the two adhesives are as described hereinwith reference to the shingle of FIGS. 1-3, as the same basic principlesof adhesion are relied upon. However, this modification delineates moreclearly some of the desired characteristics of the heat sensitiveadhesive utilized for sealing the shingles and for load bearing whilethe shingles are packaged.

Referring to FIG. 7, the shingles may be packaged with the first threeshingles 40, 41, 42, front face-to-back face and with all the heads onone end and all the butts at the opposite end. For the purpose ofsimplicity the stripe 26 has been omitted as the non-adhering stripe maycomprise either a stripe as shown in FIG. 6 or a brushed surface asshown in FIG. 8. Subsequent shingles 43, 44, and 45, also frontface-to-back face, have their head and butt portions reversed relativeto the head and butt positions of the previously stacked shingles tolevel the bundle; otherwise, the bundle would tend to be thickeradjacent the end containing the adhesive stripe.

The adhesive stripes 23, 24 of the first shingle 40, if of equal height,theoretically support, in part, the weight of the load of the remainderof the shingles in the bundle. However, the heat sensitive adhesive ofstripe 23 actually supports the load since it is preferably hard andtough at room temperatures and thereabouts, thereby protecting thepressure sensitive stripe 24 from being subjected to the load. As aresult, the pressure sensitive adhesive may be formulated from materialsthat are relatively soft at room temperatures, or thereabouts, sincethere is no danger of the latter adhesive spreading under the action ofa shingle load, unless, of course, it is made initially higher than theheat sensitive adhesive. In such a construction, the pressure sensitiveadhesive will spread slightly until the adhesive levels areapproximately the same at which time the load is borne by the heatsensitive adhesive.

This hard and tough characteristic at room temperatures, or thereabouts,is utilized to excellent advantage during sealing of the shingles. Thus,after the shingles are laid to form a roof covering, the shingles areeventually subjected to temperatures, wherein an effective flow of theheat sensitive adhesive occurs. The tabs of overlying shingles areeffectively wetted, and, since the adhesive also becomes tacky, they areadhesively tacked to the underlying shingles, thereby forming thepermanent bond between the shingles. This bond is maintained uponlowering of roof temperatures, which would occur, for example, duringcooler summer weather or during the winter months. Thus, this hardnesscharacteristic of the heat sensitive adhesive serves a two-foldfunction; the first, to bear the brunt of the load-bearing while theshingles are bundled and therefore to relieve its adhesive mate fromthis duty, and the second, eventually to create the strong, permanentadhesive bond between shingles after the shingles are laid to form aroof covering.

Referring back to FIGS. and 6, the two stripes 23, 24 are superimposedupon the face 21 with each adhesive entering the crevices between thegranules firmly bonding itself to the shingle face 21 The width of thestripes ordinarily is in the range of approximately A"-2", while thethickness of each varies between approximately 1-20 mils. A releasepaper 27 is used to cover the stripes, as described. The manner ofapplication of the stripes may be the same as described with respect tothe shingle illustrated in FIGS. 1-3. However, the solvent emulsionsystem is not suitable for application of the pressure sensitiveadhesive, since no beneficial surface, i.e., a planar surface, ispresent as in the embodiment illustrated in FIGS. 1-3.

The shingles are laid on a roof deck to form the roof covering asdescribed in relation to FIG. 4. Since the asphalt shingles are flexiblein nature, good contact is obtained between the upper surface of thepressure sensitive stripe 24 and the overlying tab or tabs, and throughmolecular action, an immediate adhesive bond occurs between overlappingsurfaces via the action of the adhesive of stripe 24. When effectivetemperatures are obtained, subsequent to the time of laying of theshingles, the adhesive of stripe 23 becomes noticeably effective to Wetthe overlapped surfaces and eventually to create the permanent adhesivebond between shingles as described herein.

Although the shingles have been described as being packaged frontface-to-back face (or often referred to merely as face-to-back), it isevident that other relative shingle relationships may be utilized inpackaging. Often, this relationship is governed by the relativepositions on the shingles of the adhesive stripes 3, 4 or 23, 24. Thus,for example, the shingles may also be bundled front faceto-front face inpairs, or back-to-back in pairs.

The pressure sensitive adhesive, in any of the modifications, can beapplied at high machine speeds in a high production system utilizing thesystems of application, noted herein. Consequently, heavy dutyequipment, oftentimes used in applying a combination pressure sensitiveand heat sensitive adhesive to asphalt shingles, is, therefore, notrequired.

While the invention has been described in rather full detail, it will beunderstood that these details need not be strictly adhered to and thatvarious changes and modifications may suggest themselves to one skilledin the art,

14 all falling Within the scope of the invention as defined by thesubjoined claims.

What I claim is:

1. A self-sealing shingle comprising a band of predominantly heatsensitive adhesive adhering to a major face of the shingle, saidadhesive having a minimum softening point of F. and a penetration at 77F., 10-0 gr., 5 sec., in the range of 0-35, and a distinct band ofpredominantly pressure sensitive adhesive adjacent the first band, saidpressure sensitive adhesive being in tacky condition at temperaturesabove 0 F.

2. A self-sealing shingle as recited in claim 1, wherein both thepressure sensitive and heat sensitive adhesivev bands are in engagementwith said major face of the shingle.

3. A self-sealing shingle as recited in claim 2, wherein at least one ofthe adhesive bands comprises spaced areas of adhesive.

4. A self-sealing shingle as recited in claim 1, wherein the pressuresensitive adhesive band is superimposed over a portion of the heatsensitive adhesive band, whereby both pressure sensitive and heatsensitive adhesives present substantial areas of exposed surface.

5. A self-sealing shingle as recited in claim 4, wherein the pressuresensitive adhesive band comprises spaced areas of adhesive.

6. A process for manufacturing self-sealing asphalt roofing shinglescomprising the steps of adhering to a major surface of the shingle astripe of predominantly heat sensitive adhesive, superimposing a stripeof predominantly pressure sensitive adhesive to a strip of antistickmaterial, the surface area of the pressure sensitive adhesive beingsubstantially less than the surface area of the heat sensitive adhesive,placing the strip of material "upon the heat sensitive adhesive stripeof adhesive so that the adhesive stripes mate with each other, andremoving the anti-stick material, leaving at least a major Pontion ofthe pressure sensitive adhesive mating with the heat sensitive stripe.

7. A process for manufacturing self-sealing shingles as recited in claim6, wherein the pressure sensitive stripe of adhesive comprises spacedareas of adhesive.

8. A process for manufacturing self-sealing shingles as recited in claim6, wherein the thickness of the pressure sensitive adhesive stripe issubstantially less than the thickness of the heat sensitive adhesivestripe.

References Cited in the file of this patent UNITED STATES PATENTS600,745 Sands Mar. 15, 1898 2,210,209 Kirschbraun Aug. 6, 1940 2,666,402Clarvoe Jan. 19, 1954 2,721,810 Schram Oct. 25, 1955 2,863,405 Leibrooket al Dec. 9, 1958 2,935,416 Dunbar et a1 May 3, 1960

1. A SELF-SEALING SHINGLE COMPRISING A BAND OF PREDOMINANTLY HEATSENSITIVE ADHESIVE ADHERING TO A MAJOR FACE OF THE SHINGLE, SAIDADHESIVE HAVING A MINIMUM SOFTENING POINT OF 140*F. AND A PENETRATION AT77*F., 100 GR., 5 SEC., IN THE RANGE OF 0-35, AND A DISTINCT BAND OFPREDOMINANTLY PRESSURE SENSITIVE ADHESIVE ADJACENT THE FIRST BAND, SAIDPRESSURE SENSITIVE ADHESIVE BEING IN TACKY CONDITION AT TEMPERATURESABOVE 0*F.